Engine casing treatment for reducing circumferentially variable distortion

Abstract

A rotary component for a gas turbine engine defining a central axis extending along an axial direction, a radial direction extending perpendicular to the axial direction, and a circumferential direction perpendicular to both the central axis and the radial direction. The rotary component includes a plurality of rotor blades operably coupled to a rotating shaft extending along the central axis and an outer casing arranged exterior to the plurality of rotor blades in the radial direction and defining an annular gap between a tip of each of the plurality of rotor blades and the outer casing. The outer casing includes a plurality of features on an interior surface of the outer casing. A first feature of the feature(s) defines a first casing thickness, and a second feature positioned at least partially circumferentially or axially from the first feature defines a second casing thickness different than the first casing thickness.

Description

FIELD[0001]The present subject matter relates generally to engine casing treatments, more particularly, to engine casing treatments for reducing circumferentially variable distortion at the rotating blades of a gas turbine engine.BACKGROUND[0002]A gas turbine engine generally includes a fan and a core arranged in flow communication with one another. Additionally, the core of the gas turbine engine generally includes, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, air is provided from the fan to an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section to the turbine section. The flow of combustion gases through the turbine section drives the turbine section an...

AI Technical Summary

Problems solved by technology

Further, such distortion may be circumferentially varying around the inlet of the fan blades or the compressor blades.

Moreover, such distortion may propagate through each subsequent stage of the compressor.

Additionally, distortion may be created at the fan blades and / or stages of the compressor and propagate to subsequent stages of the compressor.

Such distortion may affect the stall point of the compressor or the fan assembly.

Stall on the compressor and / or fan blades may generally reduce the efficiency of the engine.

For example, compressor stalls may reduce the compressor pressure ratio and reduce the airflow delivered to a combustor, thereby adversely affecting the efficiency of the gas turbine.

Following rotating stall, the compressor may transition into a surge condition or a deep stall condition that may result in a loss of efficiency and, if allowed to be prolonged, may lead to failure of the gas turbine.

Images